Electricity
In a series circuit, three resistors have values of 4 ohms, 6 ohms, and 8 ohms. If a potential difference of 9 volts is applied across the circuit, calculate the current flowing through the circuit.
The current is I = 0.5 A
A car travels a distance of 150 kilometers in 2.5 hours. Calculate the average speed of the car.
v = 60 km/hr.
The initial speed of a toy car is Vi = 6m/s.
Determine the time needed by it to stop if it decelerates uniformly with a = -1m/s2.
The time needed is 6sec.
If an object is moving to the right at a constant velocity, what can you conclude about the forces acting on it according to Newton's First Law?
The forces along the vertical and those along the horizontal are of the same magnitude but of opposite directions.
You have a 120-watt light bulb operating at a potential difference of 100 volts. Calculate the current flowing through the bulb and the resistance of the bulb.
The current is I = 1.2 A
The resistance is R = 83.33 Ohms
A car accelerates from rest to a speed of 30 meters per second in 6 seconds. Calculate the car's acceleration.
a = 5 m/s2
The initial speed of a toy car is Vi = 5m/s.
It accelerates uniformly with a = 2m/s2 for 3 sec.
Determine the distance covered by the toy car during 3sec.
The distance covered by the toy car is 24m.
If you apply a net force of 3 N on 100 g-box, what is the acceleration of the box?
The acceleration of the box is 30 m/s2.
If you have a variable resistor (rheostat) and you want to vary the current in a circuit from 0.5 amperes to 2 amperes while keeping the potential difference constant at 12 volts, what should be the resistance range of the variable resistor?
The resistance ranges between 6 ohms and 24 ohms
A cyclist rides 10 kilometers in 30 minutes and then 8 kilometers in 15 minutes. Calculate the cyclist's average speed in meters per second (m/s).
v = 6.66 m/s
An object moves, from rest, with a uniformly accelerated rectilinear motion. It covers 20m within 2sec.
Determine the acceleration of the object.
The acceleration of the object is 5m/s2.
When the force applied to a moving object is equal and opposite the force of friction acting on it, what happens to the object?
It moves with a constant speed.
The characteristic equation of an electric generator is:
I = -0.5U + 2 (SI units)
Determine the characteristics of this electric generator.
E = 4V
r = 2 ohms
The position of an object at t=0sec is xi = -5m and its position at t=2sec is xf = 5m.
Determine the displacement of the object between t=0sec and t=2sec.
The displacement is 10m.
The speed of an object increases from 8m/s till reaching 10m/s as it crosses a distance of 6m.
Determine the acceleration of the object.
The distance covered by the object is 3m/s2.
A car, of mass 950kg, slows down as it approaches a traffic light. The car was moving at 13.5m/s and it takes it 22sec to stop.
Determine the force required to stop the car.
The magnitude of the car is 583N opposite to the direction of motion.
A battery (r=1ohm, E=12V) is connected across a motor ( r1=2 ohms, e=3V).
Determine the current flowing in the circuit.
I = 3A
An object accelerates uniformly at 2m/s2 as it moves along a straight path. Determine the speed of the car at t=4sec if its initial speed at t = 0sec is 1m/s.
The speed of the car is 9m/s.
The motion of an object is described by:
Phase One:
The speed of the object increases from 0m/s to 1m/s during 1sec.
Phase Two:
The object moves at a constant speed of 1m/s for 1sec.
Determine the total distance covered by the object during the two phases.
The distance covered is 1.5m.
Derek pushes a 10kg crate along a rough surface with 35N of force. He observes that it is only accelerating at a rate of 2m/s2.
What must the value of the force of friction be?
The magnitude of friction is 15N